On January 18, the lowest unit charge window for Presidential primaries or caucuses begins in Super Tuesday states including Alabama, American Samoa (D), Arkansas, California, Colorado, Maine, Massachusetts, Minnesota, North Carolina, Oklahoma, Tennessee, Texas, Utah, Vermont, and Virginia. The LUC window opened on January 15 for South Carolina’s Democratic primary and will open on January 23 for stations in Puerto Rico. Soon behind, on January 25, lowest unit charge windows for presidential contests open in Hawaii, Idaho, Michigan, Mississippi, Missouri, North Dakota (D), and Washington State. The window opens on January 27 in the US Virgin Islands and West Virginia. January 29th is the opening of the window for contests in Guam (R), N. Mariana Islands (D) and Wyoming (R).
In these windows, when broadcasters sell time to candidates for ads in connection with the races to be decided on these dates, they must sell them at the lowest rate that they charge commercial advertisers for the same class of advertising time running during the same time period. For more on issues in computing lowest unit rates, see our articles here, here and here (this last article dealing with the issues of package plans and how to determine the rates applicable to spots in such plans), and our Political Broadcasting Guide, here.